1. Ch. 5 Glaciers & Ice Ages
p guided notes

2. Glaciers: a part of two basic cycles in the Earth system
Glaciers are a part of both the ________ cycle and _________ cycle
Glacier Definition:

3. Glaciers: a part of two basic cycles in the Earth system
2 Types of glaciers
1) Valley, or alpine glaciers:
_______________________________
_________________________________
2) Ice sheets, or continental glaciers
__________________________________
Other types
Ice caps and piedmont glaciers

4. What kind of Glaciers cover these regions
What kind of Glaciers cover these regions? How are they different than the other type?

5. How Glaciers Move 2 Types of glacial movements Zone of fracture
Plastic flow: ___________________________
Slipping along the ground: _________________
Average rate of movements very slow up to ______ m a day
Zone of fracture
Uppermost _____ meters
____________form in brittle ice

6. Explain…where is it moving fastest? Why does it fracture on top?

7. Glacial Movement Glacial Budget: _____________________
___________________________________
Zones of a Glacier
Zone of accumulation –
Zone of wastage –

8. What causes the glacier to advance or retreat?
Figure 6.6

9. Glacial Erosion Glaciers erode by __________ – lifting of rock blocks
Abrasion: ___________________
Evidence of Abrasion:
_______________
________________

10. Glacial Erosion: Erosional Landforms
Landforms created by alpine glacial erosion: define and describe how formed
Glacial trough/U-shaped valley:_________
Hanging valley: _________________
Cirque: _____________________
Arête:__________________
Horn:___________________
Fjord:___________________________

11. Label the Erosional landforms created by alpine glaciers
Figure 6.9 C

12. What causes glaciers to deposit material?

13. Glacial Erosion: Depositional Features
Types of glacial drift (sediment of glacial origin)
______ – material that is deposited directly by ice
_______________ - sediment deposited by meltwater
Glacial erratics: ______________________

14. What evidence is there that this is glacial till and not river deposited sediment?
Close up of pebble

15. Glacial Erosion: Depositional Features
Moraines :_________________________
How are each of the following formed?
Types of moraines
Lateral
Medial
End
Ground

16. Glacial Erosion: Depositional Features
Define and explain the formation of each depositional feature
Outwash plain
Kettles
Drumlins
Eskers
Kames

17. Label the depositional features
Figure 6.18

18. A drumlin in upstate New York… What might you look for on a topographic map of Wellesley to determine if we had any drumlins?

19. Glaciers of the Ice Age
Alternative explanations given for glacial sediment:_______________________
_________________________
Glacial/interglacial cycles occur every __________
Our “Ice age” contained about _____ cycles
Ice Age
Began 2 to 3 million years ago
Division of geological time is called the __________epoch
Ice covered ______ of Earth's land area

20. Maximum extent of ice during the Ice Age: How do we know?
Figure 6.19

21. Causes of Glaciation Proposed possible causes
Plate Tectonics which could cause a climate shift by ______________________
___________________________________
_____________________________
Variations in earth’s orbit which could cause a climate shift by______________________
______________________________________

22. Variations in earth’s orbit
________________ hypothesis
Shape (____________) of Earth's orbit varies
Angle of Earth's axis (___________) changes
Axis wobbles (_____________)
Changes in climate over the past several hundred thousand years are closely associated with variations in Earth's orbit